Best AI browser extensions and in-browser AI agents for 2026
An AI browser extension adds an assistant to the page you are reading: it summarises, drafts replies, explains terms and saves what matters. An in-browser AI agent goes further and operates the browser itself, clicking, typing and moving between pages to finish a task. In 2026 the best setup for most people is one good extension for daily reading and writing, plus an agent for the repetitive web tasks that eat an hour each week.
I first published this list in April 2025, when it was all extensions for meetings, video summaries and writing. A lot has changed since then. Agents that use a browser like a person went from demos to products you can rely on for real work, and several of them are listed on AI Agents Live. This update covers both groups, with what each tool is good at. If you are thinking about switching to a whole AI browser instead, I compare those in AI browsers and the future of browsing.
AI browser extensions for everyday work
These live in your browser toolbar or sidebar and work on the page in front of you.
HARPA AI is an automation agent for Chrome with a 4.5 rating on AI Agents Live. It summarises articles and videos, drafts email replies in Gmail, shows AI answers next to Google results with sources, monitors prices and extracts data from pages. It sits on the line between an extension and an agent, which makes it a good first install.
SummaryTube summarises YouTube videos with key points and transcripts, and its Chrome extension does it on the YouTube page itself. Use it to decide whether a long talk is worth an hour.
AI Term Highlighter scans the page, highlights difficult terms and explains each one in context when you click it. It is a quiet helper when you read outside your field, such as a marketer reading a machine learning paper.
remio saves what you read on the web into a personal knowledge base, with highlights and search across everything you saved. It suits researchers and anyone who reads a lot and forgets where they read it.
ReviewResponder helps you write replies to customer reviews, and its extension works directly on review pages such as Google, Yelp, TripAdvisor and Trustpilot. Small business owners save a lot of time here.
In-browser AI agents that do the clicking
These agents operate a browser: they open pages, fill in forms, click buttons and read the results.
Anchor Browser is a platform for agentic browser automation with a 4.7 rating on AI Agents Live. It turns web tasks on sites with little or no API into automations you can call like an API, which suits teams that collect data or run the same web workflow every day.
Browser Use is an open source library that connects AI agents to a browser. Developers use it to let an agent navigate, read page structure, manage tabs and run custom actions.
Stagehand is an open source framework for web agents with three simple building blocks: act, extract and observe. It suits developers who want to mix written code with natural language steps in the same script.
OpenAI's Operator, an early agent of this kind, became the agent mode inside ChatGPT in July 2025. OpenAI has since moved its browsing agent into the ChatGPT desktop app and a Chrome extension, so people who use ChatGPT already have a browsing agent at hand.
How to choose
- If you want help reading and writing, start with one extension that covers summaries and replies, such as HARPA AI.
- If you watch a lot of video, add a YouTube summariser.
- If you repeat the same web task every week (pulling reports, updating listings, checking prices), try an in-browser agent on that one task.
- If you are a developer building a product, pick a library or framework such as Browser Use or Stagehand and keep the agent's steps in your code.
Use them safely
Extensions can read the pages you visit, and agents can act on them. Give them the smallest access that works. Install extensions from the official store, check the permissions they ask for, and remove the ones you stop using.
Run agents in a separate browser profile without your saved passwords, at least while you test them. Web pages can contain hidden instructions aimed at an agent, a risk known as prompt injection, so keep a person approving any step that pays, sends or deletes.
Questions people ask
What is the difference between an AI browser extension and an AI browser agent?
An extension assists you on the page you are on, and you stay in control of every click. An agent takes a goal and carries out the clicks and typing itself across several pages.
Are AI browser extensions safe?
They are as safe as the permissions you give them and the company behind them. Read the permissions, check the privacy policy, and use extensions from makers you can identify.
Which in-browser AI agent is best for developers?
Browser Use and Stagehand are both open source and built for developers. Stagehand fits teams who like code with natural language steps, and Browser Use fits agents that explore a site more freely.
The Browser AI Agent and Web Interaction Agent categories on AI Agents Live list these tools with their reviews.
